Cloud Computing at IFCA

Introduction

This is a beta service, since the deployment and development is ongoing. However, to test the functionality, access to the infrastructure can be granted to certain users.

We highly recommend to check this document frequently, since changes in the documentation may occur.

Managing the cloud is made from the GRIDUI Cluster. Ensure that you have the credentials properly installed by issuing the following command and checking that it returns something:

$ echo $NOVA_API_KEY

It should return a string. If you do not see anything, please open an incidence.

Create a machine

To create a machine you have to perform several steps:

• Decide which of the pre-built images you are going to use.
• Decide which with of the available sizes is suitable for you.
• Decide (and create if not ready) with keypair should be used to connect to the machine.

Image and size selection

Image selection

There are several pre-built images available. To check them, use the euca-describe-images command:

$ euca-describe-images 
IMAGE   ami-00000008    None (cloudpipe)                available       public                  machine                 instance-store
IMAGE   ami-00000007    None (Debian Wheezy (2011-08))          available       public                  machine                 instance-store
IMAGE   ami-00000006    None (lucid-server-uec-amd64.img)               available       public                  machine                 instance-store
IMAGE   ami-00000003    None (Scientific Linux 5.5)             available       public                  machine                 instance-store
IMAGE   ami-00000001    None (Scientific Linux 5.5)             available       public                  machine                 instance-store

Once you have decided with image to use, write down its identifier (ami-XXXXXXXX).

Instance types

You can choose the size of your machine (i.e. how many CPUs and how much memory) from the following instance types:

Standard machines

High-memory machines

Create SSH credentials

For most of the users this is a one-time step (although you can create as much SSH credentials as you want). You have to create an SSH-keypair so as to inject it to the newly created machine with the following command (it will create a keypair named cloudkey and store it under ~/.cloud/cloudkey.pem):

$ euca-add-keypair cloudkey > ~/.cloud/cloudkey.pem

Make sure that you keep safe the file ~/.cloud/cloudkey.pem, since it will contain the private key needed to access your cloud machines. You can check the name later with the euca-describe-keypairs command.

Launching the instance

To launch the instance, you have to issue euca-run-instances, specifying:

• wich keypair to use (in the example cloudkey).

• wich size should be used (in the example m1.tiny).

• with image should be used (in the example ami-00000001).

$ euca-run-instances -k cloudkey -t m1.tiny ami-00000001
RESERVATION     r-1zdwog0m      ACES    default
INSTANCE        i-00000048      ami-00000001                    scheduling      cloudkey (ACES, None)   2011-09-02T12:19:41Z    None    None

You can check its status with euca-describe-instances

$ euca-describe-instances i-00000048
RESERVATION     r-vmfu1xq2      ACES    default
INSTANCE        i-00000048      ami-00000001    172.16.1.8      172.16.1.8      blocked         cloudkey (ACES, cloud01)        0       m1.tiny         2011-09-02T12:15:32Z    nova

Connect to the server

Authorize SSH connections and ping

If you decide not to use a VPN, but connect to your machines trough the GRIDUI cluster, you have to authorize such connections with:

$ euca-authorize -P tcp -p 22 default
$ euca-authorize -P icmp -t -1:-1 default

SSH Connection

You have to use the private identify file that you created before (~/.cloud/cloudkey.pem) and pass it to the SSH client. To check the IP to with you should connect, check it with euca-describe-instances

$ ssh -i ~/.cloud/cloudkey.pem root@172.16.1.8

Stopping the server

Images can be stopped with euca-terminate-instances

$ euca-terminate-instances i-00000048

Using Cloud Storage

The storage in the cloud use volumes. Volumes are raw block devices that can be created dynamically with a desired size and associated with cloud images to be used as data disk. After use the data in the volume you can detach from the image and save for a later use of the persisted data.

Creating a Volume

To create a volume you have to run euca-create-volume command. For instance, to create a volume that is 100GB in size:

$ euca-create-volume -s 100 -z nova
VOLUME  vol-00000001    10      creating        2015-11-29

Using a Volume in an image

You may attach block volumes to instances using euca-attach-volume. You will need to specify the local block device name (this will be used inside the instance) and the instance identified. Currently the devices to attach the volume should be /dev/xvdc, /dev/xvdd,... /dev/xvdz. Attaching volume vol-00000001 to image i-00000001 in device /dev/xvdc si done with:

$ euca-attach-volume -i i-00000001 -d /dev/xvdc vol-00000001

One the image is running you can see the volume attached to the image with the command euca-describe-volumes.

$ euca-describe-volumes 
VOLUME  vol-00000001     100            nova    in-use  2015-11-29
ATTACHMENT      vol-0000000c    i-00000051      /dev/xvdc       

For instance, use the new volume as a ""ext4"" filesystem in a Ubuntu image. First, log into the image a check that the device is visible (as root or as ubuntu user and use sudo for commands):

server-1 $ sudo fdisk -l | grep Disk
Disk /dev/xvda doesn't contain a valid partition table
Disk /dev/xvdb doesn't contain a valid partition table
Disk /dev/xvdc doesn't contain a valid partition table
Disk /dev/xvda: 10.7 GB, 10737418240 bytes
Disk identifier: 0x00000000
Disk /dev/xvdb: 21.5 GB, 21474836480 bytes
Disk identifier: 0x00000000
Disk /dev/xvdc: 107.4 GB, 107374182400 bytes
Disk identifier: 0x00000000

Create a single ext4 partition on the device, an mount in the /srv mount point (-o sync is safe in case of image crashs):

server-1 $ sudo mkfs.ext4 /dev/xvdc
(...)
server-1 $ sudo mount -t ext4 -o safe /dev/xvdc /srv

Check that the volume is visible as a mounted filesystem:

server-1 $ df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/xvda             9.9G  622M  8.8G   7% /
none                  996M  144K  995M   1% /dev
none                 1001M     0 1001M   0% /dev/shm
none                 1001M   48K 1001M   1% /var/run
none                 1001M     0 1001M   0% /var/lock
none                 1001M     0 1001M   0% /lib/init/rw
/dev/xvdb              20G  173M   19G   1% /mnt
/dev/xvdc              99G  188M   94G   1% /srv

After you are done with the volume yo can detach from image with:

$ euca-detach-volume vol-00000001

You must detach a volume before terminating an instance or deleting a volume. If you fail to detach a volume, it may leave the volume in an inconsistent state and you risk losing data.

Reusing an Old Volume

Attach with the new image:

$ euca-attach-volume -i i-00000002 -d /dev/xvdc vol-00000001

Because the filesystem is already created on the volume, you only need to mount it to access:

server-1 $ sudo mount -t ext4 -o sync /dev/xvdc /srv

After you are done with the volume yo can detach from image:

$ euca-detach-volume vol-00000001

Other uses of Volumes

With volume you can create snapshots of the data, recover it, delete volumes,...etc. More on volumes http://open.eucalyptus.com/wiki/Euca2oolsStorage

Advanced topics

Attach to the project's VPN

Each project has a VPN assigned to it. You can attach any computer to it, thus having it connected to your project's internal network. So as to do so, you have to perform several steps (instructions only for GNU/Linux):

1. Copy your ~.cloud to the machine that you want to attach to your project's VPN.

2. Install OpenVPN on that machine.

3. Launch openvpn with the nova-vpn.conf configuration file.

# cd cloud_credentials
# openvpn --config nova-vpn.conf

Please note that there are several paths in the nova-vpn.conf configuration file that are relative to the directory in which it is located. Should you wish to use different/separated paths, please edit nova-vpn.conf and adjust the cert, key and ca parameters.

MacOS users may use Tunnelblick (a GUI interface to OpenVPN) that can use the nova-vpn.conf and certificate files without any changes.

# === Manage multiple credentials === # and checking that NOVA_API, NOVA_CERT, NOVA_PROJECT, NOVA_URL, NOVA_USERNAME,